Heat-expelling device with a wind guide

ABSTRACT

A heat-expelling device with a wind guide comprises a shell, a heat-generating body disposed within the front portion of the shell and a wind-blowing unit disposed within the rear portion of the shell. It further contains a wind guide at a predetermined location between the heat-generating body and the wind-blowing unit, whose outer wall includes a convex conic surface curved along the axis of and toward the heat-generating body. Thereby, the air density and the heat exchange rate can be significantly increased, and the heat generated within the heat-generating body can be delivered to the exterior of the heat-expelling device, which effectively increases the outflow air temperature and reduces the temperature of the shell.

FIELD OF THE INVENTION

The present invention relates to heat-expelling devices, more particularly to a heat-expelling device with a wind guide applied to a hot wind blower. It is featured by a wind guide capable of facilitating efficient outward delivery of heat generated in a heat-generating body, whereby the temperature of the outgoing airflow will be high and that of an outer shell will be low.

BACKGROUND OF THE INVENTION

A heat-expelling device of the prior art, such as the wind blower shown in FIG. 1, comprises fan/motor set 10, a heat-generating body 11 and a shell 12. The performance of the heat delivery and the durability of the heat-expelling device are determined by the heat exchange rate between the heat-generating body 11 and the fan/motor set 10. Particularly, the heat exchange rate of a hot-wind blower (operation temperature is 400-600° C.) should be good enough to prevent meltdown of the chrome-nickel wiring of the heat-generating body 11 due to deficient heat exchange condition. To attain good heat exchange, the following conditions have to be satisfied:

1. that the contact surface between the outgoing airflow and the combined structure of the heat-generating body 11 and the fan/motor set 10 should be large enough;

2. that the contact time between the heat-generating body 11, preferably being of the shape of an elongated barrel, and the outgoing airflow should be long;

3. that the density of the airflow passing through the heat-generating body 11 should be high (High speed of the airflow does not mean high air density.).

As shown in FIGS. 1A and 1B, the conventional heat-generating body 11 is a bracket 13 composed of a multitude of mica sheets each having a semicircle slot for housing the coil 110 of the heat-generating body 11. There are further ceramic blocks 14 disposed between bracket 13 and the coil 110 for not only preventing short circuit of the coil 110 but also reinforcing the strength of the bracket 13. Therefore, the coil 110 is wound around the circumference of the heat-generating body 11, and the wind sent from the fan/motor set 10 will be blown by the heat-generating body 11, achieving heat exchange. To enhance to heat exchange, a spoiler for pressure enhancement 15 is installed at the front end of the heat-generating body 11 facing the air outlet for dragging the airflow passing by the heat-generating body 11 so as to increase the density of the airflow. The conventional spoilers for pressure enhancement cannot effectively enhance heat exchange however; a spoiler for pressure enhancement, such as the part 15, will drag the air ejection but at the same time will induce a reverse airflow that brings extra noises and reduces the efficiency of the fan/motor set 10. Therefore, a spoiler for pressure enhancement of the prior art cannot effectively enhance the heat exchange rate of the fan/motor set 10.

Accordingly, the incapability of enhancing heat exchange will make impossible a fast delivery of heat produced in the heat-generating body 11 and will cause overheating of the heat-generating body 11. Further, the shell of the hot-wind blower will be high.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a heat-expelling device with a wind guide for enhancing heat-exchange efficiency by achieving a faster heat out-delivery, whereby the temperature gradient between the heat-generating body and the air outlet is reduced. Thereby, heat will not be stored in large quantities within the heat-generating body, and the temperature of the shell can be reduced for protecting the user.

The wind guide is made according to the types of heat expelling devices and can be flexibly installed between the heat-generating body and the wind-expelling unit, for increasing the pressure of the airflow in contact with the heat-generating body and therefore the heat exchange rate. The wind guide is easy to install and can be selected from a variety of shapes.

The wind guide is located between a heat-generating body and a wind-expelling unit, whereby the heat generated in the heat-generating body will be isolated from the wind-expelling unit, protecting the motor and the power circuit of the unit from thermal radiation. Therefore, the temperature of the wind-expelling unit will not be too high to affect the durability thereof. Since the heat-generating body and the wind-expelling unit share the same power source, the power shutdown of the heat-generating body, a necessary measure after using for an extended period of time, will also terminate the operation of the wind-expelling unit, and therefore will cause heat accumulation in the heat-generating body and the associated temperature rise. The wind guide of the present invention can isolated the device into a cold zone and a hot zone, protecting the inner parts of the present invention from thermal damage.

The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a heat-expelling device of the prior art.

FIG. 1A is a perspective view of the heat-generating body in the heat-expelling device in FIG. 1.

FIG. 1B is the C-C′ cross-sectional view corresponding to the C-C′ line in FIG. 1A.

FIG. 2 is an exploded perspective view of a heat-expelling device with a wind guide of the present invention.

FIG. 3 is a side cross-sectional view of the heat-expelling device with a wind guide in FIG. 2.

FIG. 4 illustrates the guiding of the airflow in the first preferred embodiment.

FIG. 4A is an exploded perspective view of the second preferred embodiment of the present invention.

FIG. 4B illustrates the guiding of the airflow in the second preferred embodiment.

FIG. 5 is an exploded perspective view of the third preferred embodiment of the present invention.

FIG. 6 illustrates the guiding of the airflow in the third preferred embodiment.

FIG. 7 is an exploded perspective view of the fourth preferred embodiment of the present invention.

FIG. 8 illustrates the guiding of the airflow in the fourth preferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 2, 3, a heat-expelling device with a wind guide according to the present invention comprises a shell 2, a heat-generating body 3 installed in a front portion of the shell 2 and a wind-expelling unit 4 installed in a rear portion of the shell 2. The shell 2 further comprises a bracket 31 made of mica sheets and an electro-thermal resistor 32 being a coil of high impedance. The electro-thermal resistor 32 is wound around the bracket 31; if it is necessary, ceramic blocks can be added between the bracket 31 and the electro-thermal resistor 32 for not only preventing the coil from short circuit but also reinforcing the structure of the bracket 31. If it is necessary, a spoiler for pressure enhancement 34 can be added to the heat-generating body 3. The wind-expelling unit 4 further comprises a motor 41 and a fan 42; the fan 42 is driven by the motor 41, whereby a directional airflow will be generated to blow upon the heat-generating body 3. The main feature of the present invention is a wind-guide 5 between the heat-generating body 3 and the wind-expelling unit 4, as the first preferred embodiment shown in FIG. 2 to 4. The wind-guide 5, made of a metallic material or a heat-resistant plastic material, is installed in a rear portion of the heat-generating body 3 and in front of the wind-expelling unit 4. The wind-guide 5 has a slightly conic surface with a predetermined curvature curved from the wind-expelling unit 4 toward the heat-generating body 3, being convex along the axis of the heat-generating body 3. The base surface is smaller than the cross section area of the heat-generating body 3, whereby the wind-guide 5 will guide the airflow ejected from the wind-expelling unit 4 to the circumference of the heat-generating body 3, and whereby the air pressure and density around the circumference are substantially increased, as shown in FIG. 4. Simultaneously, the outlet temperature of the airflow will be increased by more efficient heat exchange, and the temperature of the heat-generating body 3 is accordingly reduced. Therefore, a heat-expelling device with a wind guide can eject hotter airflow than the conventional device operating at the same power does.

Referring to FIGS. 4A and 4B, the second preferred embodiment of the present invention is similar to the first preferred embodiment, except that the wind-guide 5′ is installed within a shell 2′ of smaller type. The heat-expelling device with the wind guide 5′ comprises a heat-generating body 3′, a wind-expelling unit 4′ and the wind-guide 5′. Again, the wind-guide 5′, being a conic body, locates between the heat-generating body 3′ and the wind-expelling unit 4′ for guiding the airflow ejected from the wind-expelling unit 4′ to the circumference of the heat-generating body 3′, whereby the air pressure there is enhanced. The heat exchange efficiency of the heat-generating body 3′ is therefore enhanced.

Referring to FIGS. 5 and 6, the third preferred embodiment of the present invention comprises a shell 2 a, a heat-generating body 3 a, a wind-expelling unit 4 a and a wind-guide 5 a; the wind-guide 5 a is installed between the heat-generating body 3 a and the wind-expelling unit 4 a. The wind-guide 5 a is a conic body for guiding the airflow ejected from the wind-expelling unit 4 a to the circumference of the heat-generating body 3 a, whereby the air pressure there is enhanced. The heat exchange efficiency of the heat-generating body 3 a is therefore enhanced.

Referring to FIGS. 7 and 8, the fourth preferred embodiment of the present invention comprises a shell 2 b, a heat-generating body 3 b, a wind-expelling unit 4 b and a wind-guide 5 b; the wind-guide 5 a is installed between the heat-generating body 3 b and the wind-expelling unit 4 b. The wind-guide 5 b is a conic body for guiding the airflow ejected from the wind-expelling unit 4 b to the circumference of the heat-generating body 3 b, whereby the air pressure there is enhanced. The heat exchange efficiency of the heat-generating body 3 b is therefore enhanced.

The present invention is thus described, and it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. 

1. A heat-expelling device with a wind guide, comprising: a shell; a heat-generating body disposed within a front portion of said shell; a wind-blowing unit disposed within a rear portion of said shell; and a wind guide disposed at a predetermined location between said heat-generating body and said wind-blowing unit, said wind guide having an outer wall including a convex conic surface centered along an axis of said heat-generating body and being curved outwardly from said wind-blowing unit to said heat-generating body.
 2. The heat-expelling device with a wind guide of claim 1 wherein said wind-guide is connected to a rear portion of said heat-generating body and located in front of said wind-expelling unit at a predetermined location.
 3. The heat-expelling device with a wind guide of claim 1 wherein said wind-guide is formed in the front of said wind-expelling unit, between said heat-generating body and said wind-expelling unit.
 4. The heat-expelling device with a wind guide of claim 1 wherein said wind-guide is integrally formed within said shell between said heat-generating body and said wind-expelling unit.
 5. The heat-expelling device with a wind guide of claim 2 wherein said wind-guide further includes a bracket consisting of mica sheets and a electro-thermal resistor coil of high impedance wound around said bracket.
 6. The heat-expelling device with a wind guide of claim 3 wherein said wind-guide further includes a bracket consisting of mica sheets and a electro-thermal resistor coil of high impedance wound around said bracket.
 7. The heat-expelling device with a wind guide of claim 4 wherein said wind-guide further includes a bracket consisting of mica sheets and a electro-thermal resistor coil of high impedance wound around said bracket.
 8. The heat-expelling device with a wind guide of claim 2 wherein said wind-expelling unit further comprise a fan and a motor.
 9. The heat-expelling device with a wind guide of claim 3 wherein said wind-expelling unit further comprise a fan and a motor.
 10. The heat-expelling device with a wind guide of claim 4 wherein said wind-expelling unit further comprise a fan and a motor.
 11. The heat-expelling device with a wind guide of claim 2 wherein said wind-guide is made of a material selected from a metallic material and a heat-resistant plastic material.
 12. The heat-expelling device with a wind guide of claim 3 wherein said wind-guide is made of a material selected from a metallic material and a heat-resistant plastic material.
 13. The heat-expelling device with a wind guide of claim 4 wherein said wind-guide is made of a material selected from a metallic material and a heat-resistant plastic material.
 14. The heat-expelling device with a wind guide of claim 2 wherein said wind-guide has a convexly conic surface curved about an axis extended from and toward said heat-generating body and a bottom surface smaller than the cross section of said heat-generating body.
 15. The heat-expelling device with a wind guide of claim 3 wherein said wind-guide has a convexly conic surface curved about an axis extended from and toward said heat-generating body and a bottom surface smaller than the cross section of said heat-generating body.
 16. The heat-expelling device with a wind guide of claim 4 wherein said wind-guide has a convexly conic surface curved about an axis extended from and toward said heat-generating body and a bottom surface smaller than the cross section of said heat-generating body. 